Substrates such as wafers for semiconductor devices and glass substrates for either display units or thin film solar cells are manufactured through several processes. At the time, substrates are loaded to, and processed at, a substrate processing device which provides optimal conditions required for each process.
Today, a cluster-type substrate processing device that may process substrates in batches has been developed and used to improve productivity.
The cluster-type substrate processing device includes a load lock chamber where substrates are stored, a transfer chamber for transferring substrates, and multiple process chambers for performing respective processes. An apparatus for transferring substrates which is installed in the transfer chamber generally at a vacuum state transfers substrates between the load lock chamber and the transfer chamber, or between the transfer chambers.
A substrate apparatus for transporting substrates published in Korea Laid-Open Publication No. 10-2009-0008400 folds or unfolds an articulated arm 31 by using a belt drive system 38 and transfers substrates to be treated while a hand 32 makes a linearly reciprocating motion due to the articulated arm 31. However, because the apparatus for transporting substrates folds or unfolds the articulated arm 31 by using the belt drive system 38, one side of the belt drive system 38 must be necessarily exposed to the outside. This may threaten to cause the substrates to be damaged by particles generated from the belt drive system 38.
A conveyance robot which solves such a problem is disclosed in Japanese Patent No. 4364001.
The conveyance robot is installed to allow an axis 31A formed on one end of a first link arm 31 to be rotatable on a swivel base 300 by a driving unit such as a motor, and the other end of the first link arm 31 is installed to an intermediate link 33 to be rotatable. One end and the other end of a second link arm 34 are installed to a linear motion unit 20 and to the intermediate link 33, respectively, to be rotatable.
As the first link arm 31 is normally or reversely rotated based on the center 01 of the axis 31A, the first link arm 31 and the second link arm 34 are mutually folded or unfolded based on the intermediate link 33 and this causes the linear motion unit 20 to give linear reciprocating motions. The linear motion unit 20 has multiple hands 21 on which works W are loaded and supported.
Since the first link arm 31 of the conveyance robot is rotated based on the axis 31A that is supported by a swivel base 300, when the other end of the first link arm 31 and that of the second link arm 34 are combined together to be rotatable, and the virtual linear line connecting both ends of the first link arm 31 and that connecting both ends of the second link arm 34 are overlapped to become at the state of singularity, the second link arm 34 may also threaten to be rotatable due to the rotation of the first link arm 31. As the first link arm 31 and the second link arm 34, then, cannot be folded or unfolded, the linear motion unit 20 cannot give linear motions.
To prevent this, the other end of the first link arm 31 and that of the second link arm 34 of the conveyance robot are installed to the intermediate link 33 to be rotatable by being made to be mutually separated and one end and the other end of a separate ancillary link arm 32 are installed to the swivel base 300 and the intermediate link 33 to be rotatable.
As shown above, the conventional conveyance robot may increase the costs due to its complicate structure.